U.S. patent application number 09/683055 was filed with the patent office on 2003-05-15 for two speed supercharger drive.
This patent application is currently assigned to Ford Global Technologies, Inc.. Invention is credited to Janson, David Allen.
Application Number | 20030089348 09/683055 |
Document ID | / |
Family ID | 24742373 |
Filed Date | 2003-05-15 |
United States Patent
Application |
20030089348 |
Kind Code |
A1 |
Janson, David Allen |
May 15, 2003 |
Two speed supercharger drive
Abstract
A two speed supercharger system (20) for an internal combustion
engine. The supercharger system includes a supercharger pump (40)
that is driven by the engine via a gear box (34). The gear box
includes two planetary gear sets (54, 70) and a controllable clutch
(66). A controller (35) selectively activates the clutch to control
the transition between the two speeds to assure a smooth transition
without sudden changes in torque output.
Inventors: |
Janson, David Allen;
(Plymouth, MI) |
Correspondence
Address: |
MACMILLAN, SOBANSKI & TODD, LLC
ONE MARITIME PLAZA - FOURTH FLOOR
720 WATER STREET
TOLEDO
OH
43604
US
|
Assignee: |
Ford Global Technologies,
Inc.
Suite 600 Parklane Towers East One Parklane Boulevard
Dearborn
MI
|
Family ID: |
24742373 |
Appl. No.: |
09/683055 |
Filed: |
November 13, 2001 |
Current U.S.
Class: |
123/559.1 |
Current CPC
Class: |
F02B 33/40 20130101;
F02B 39/04 20130101; F02B 39/12 20130101; F04D 25/024 20130101 |
Class at
Publication: |
123/559.1 |
International
Class: |
F02B 033/00 |
Claims
1. A system for variably controlling the rotational velocity input
to a supercharger compressor that is operatively coupled to an
internal combustion engine, the system comprising: an input member
adapted to couple to a rotating member of the engine; a first
planetary gear set including a first sun gear, a first ring gear,
and a first planet carrier having a first set of planetary gears
mounted thereon and meshing with the first sun gear and the first
ring gear, with one of the first sun gear, the first ring gear and
the first planet carrier rotationally coupled to the input shaft; a
clutch mechanism having a first portion that is rotationally fixed
relative to the engine, and a second portion that is selectively
rotationally fixed relative to the first portion, with the second
portion being rotationally coupled to one of the first sun gear,
the first ring gear and the first planet carrier that is not
coupled to the input shaft; a one-way clutch coupled between one of
the first sun gear, the first ring gear and the first planet
carrier that is coupled to the input shaft, and another of the
first sun gear, the first ring gear and the first planet carrier
that is not coupled to the input shaft; a second planetary gear set
including a second sun gear, a second ring gear and a second planet
carrier having a second set of planetary gears mounted thereon and
meshing with the second sun gear and the second ring gear, with one
of the second sun gear, the second ring gear and the second planet
carrier rotationally fixed to one of the first sun gear, the first
ring gear and the first planet carrier that is not directly
rotationally coupled to the input shaft; an output member adapted
to couple to an input shaft to a supercharger and coupled to one of
the second sun gear, the second ring gear and the second planet
carrier; and a controller for selectively actuating the clutch
mechanism.
2. The system of claim 1 wherein the controller includes
electronics for variably controlling the clutch during transition
back and forth between different gear ratios.
3. The system of claim 1 wherein the clutch mechanism is an
electromagnetic particle clutch.
4. The system of claim 1 wherein the clutch mechanism is an
electric ball/ramp clutch.
5. The system of claim 4 wherein the clutch mechanism is an
electric cone clutch.
6. The system of claim 1 wherein the input shaft is coupled to the
first planet carrier, the clutch mechanism is coupled to the first
sun gear, the one-way clutch is coupled between the first planet
carrier and the first ring gear, the second plant carrier is held
from rotating, and the second sun gear is coupled to the output
member.
7. The system of claim 1 wherein the input shaft is coupled to the
first planet carrier, the clutch mechanism is coupled to the first
ring gear, the one-way clutch is coupled between the first planet
carrier and the first sun gear, the second planet carrier is held
from rotating, and the second sun gear is coupled to the output
member.
8. The system of claim 1 wherein the input shaft is coupled to the
first planet carrier, the clutch mechanism is coupled to the first
ring gear, the one-way clutch is coupled between the first planet
carrier and the fir sun gear, the second ring gear is held from
rotating, and the second sun gear is coupled to the output
member.
9. The system of claim 1 wherein the input shaft is coupled to the
first planet carrier, the clutch mechanism is coupled to the first
sun gear, the one-way clutch is coupled between the first planet
carrier and the first ring gear, the second ring gear is held from
rotating, and the second sun gear is coupled to the output
member.
10. A system for driving the input to a supercharger pump coupled
to an internal combustion engine, the system comprising: an input
member for receiving input torque from a rotating member of the
engine; a gear set for shifting between a higher gear ratio and a
lower gear ratio; a clutch for causing the shifting between the
higher gear ratio and the lower gear ratio; a controller coupled to
the clutch for variably controlling the clutch during shifting back
and forth between the higher gear ratio and the lower gear ratio to
provide a smooth transition in torque output of the internal
combustion engine; and an output member coupled to the gear set and
adapted to couple to the supercharger pump for driving the
pump.
11. The system of claim 10 wherein the gear set includes a first
planetary gear set coupled to the input member, a second planetary
gear set coupled between the first planetary gear set and the
output member.
12. The system of claim 10 wherein the clutch is an electromagnetic
particle clutch.
13. The system of claim 10 wherein the clutch is an electric
ball/ramp clutch.
14. The system of claim 10 wherein the clutch is an electric cone
clutch.
15. A method for controlling the input speed to a drive shaft of a
supercharger pump coupled to an internal combustion engine
comprising the steps of: receiving input torque from a rotating
member of the engine; providing a gear set shiftable between a
higher gear ratio and a lower gear ratio; providing a clutch for
causing a shift between the higher gear ratio and lower gear ratio;
variably controlling the clutch while shifting back and forth
between the higher gear ratio and the lower gear ratio to provide a
smooth transition in torque output for the internal combustion
engine; and providing an output member coupled between the gear set
and the supercharger pump.
16. The method of claim 15 wherein the clutch is variably
controlled by modulating the clutch on and off.
17. The method of claim 15 wherein the clutch is variably
controlled by varying limited slip in the clutch during transition
between the higher gear ratio and the lower gear ratio.
Description
TECHNICAL FIELD
[0001] The present invention relates to supercharger systems used
with internal combustion engines and more particularly to
centrifugal supercharger systems having variable speed drives.
BACKGROUND OF THE INVENTION
[0002] Superchargers employed to boost the power of internal
combustion engines are well know. The supercharger systems
typically include an air compressor that pulls in intake air and
compresses it prior to being fed into the engine cylinders. This
allows for a greater power output relative to the same size engine
without a supercharger. The air compressor is conventionally driven
by a belt that connects to a pulley on the shaft of the compressor
and a pulley on the crankshaft of the engine. There may also be a
fixed ratio gear set between the compressor and camshaft in order
to obtain one desired gear ratio. So the rotational speed and thus
the amount of compression depends solely upon the engine speed.
[0003] In particular, supercharged engines have advantages when
used in vehicles. The advantage with superchargers is that the
engine can produce more power, so for a given desired power output,
the engine with a supercharger can be smaller, thus generally
lighter weight and having better fuel economy. The drawback is that
the centrifugal supercharger system does not provide much increase
in pressure for the intake air at low engine RPMs.
[0004] Some have attempted to resolve this problem. One attempt to
overcome the drawbacks of a centrifugal supercharger system
employed a continuously variable belt drive between the drive
pulley and the driven pulley of the compressor in order to vary the
drive ratio. It used a belt mounted on cone pulleys. A pair of
cones on each pulley could be pushed together and pulled apart to
vary the drive ratio for the belt. But this proved to be too
complicated and unreliable.
[0005] Further, it is advantageous to have the centrifugal
supercharger system operate without causing a discontinuity in the
torque and horsepower. These types of discontinuities can cause the
engine to surge or lug down, which is generally objectionable to
vehicle occupants.
[0006] Thus, it is desirable to have a centrifugal supercharger
system that overcomes the drawbacks of the conventional centrifugal
supercharger system. In particular, it is desirable to have a
system with a variable drive ratio, in order to improve an engine's
torque at low RPMs, while avoiding the cost, complexity and
unreliability of previous attempts to produce such a system. And,
preferably, the variable drive ratio does not cause discontinuities
in the torque or horsepower output.
SUMMARY OF THE INVENTION
[0007] In its embodiments, the present invention contemplates a
system for variably controlling the rotational velocity input to a
supercharger compressor that is operatively coupled to an internal
combustion engine. The system includes an input shaft adapted to
couple to a rotating member of the engine, and a first planetary
gear set including a first sun gear, a first ring gear, and a first
planet carrier having a first set of planetary gears mounted
thereon and meshing with the first sun gear and the first ring
gear, with one of the first sun gear, the first ring gear and the
first planet carrier rotationally coupled to the input shaft. The
system also includes a clutch mechanism having a first portion that
is rotationally fixed relative to the engine, and a second portion
that is selectively rotationally fixed relative to the first
portion, with the second portion being rotationally coupled to one
of the first sun gear, the first ring gear and the first planet
carrier that is not coupled to the input shaft. A one-way clutch is
coupled between one of the first sun gear, the first ring gear and
the first planet carrier that is coupled to the input shaft, and
another of the first sun gear, the first ring gear and the first
planet carrier that is not coupled to the input shaft. A second
planetary gear set includes a second sun gear, a second ring gear
and a second planet carrier having a second set of planetary gears
mounted thereon and meshing with the second sun gear and the second
ring gear, with one of the second sun gear, the second ring gear
and the second planet carrier rotationally fixed to one of the
first sun gear, the first ring gear and the first planet carrier
that is not directly rotationally coupled to the input shaft. An
output shaft is adapted to couple to an input shaft to a
supercharger and coupled to one of the second sun gear, the second
ring gear and the second planet carrier; and a controller
selectively actuates the clutch mechanism.
[0008] The present invention further contemplates a method for
controlling the input speed to a drive shaft of a supercharger pump
coupled to an internal combustion engine comprising the steps of:
receiving input torque from a rotating member of the engine;
providing a gear set shiftable between a higher gear ratio and a
lower gear ratio; providing a clutch for causing a shift between
the higher gear ratio and lower gear ratio; variably controlling
the clutch while shifting back and forth between the higher gear
ratio and the lower gear ratio to provide a smooth transition in
torque output for the internal combustion engine; and providing an
output member coupled between the gear set and the supercharger
pump.
[0009] Accordingly, an object of the present invention is to
provide a supercharger system for an internal combustion engine
that includes a two speed gearbox between the drive pulley on the
engine and the driven pulley on the compressor.
[0010] Another object of the present invention is to provide
supercharger system for an internal combustion engine that includes
a two speed gearbox with a variable controlled clutch.
[0011] An advantage of the present invention is that an engine with
a two speed supercharger drive system will allow for improved
vehicle torque at low engine RPMs while maintaining its efficiency
at high engine RPMs.
[0012] Another advantage of the present invention is that the two
speed supercharger drive is a low cost and reliable system for
providing improved engine performance.
[0013] A further advantage of the present invention is that the
drive ratio of the supercharger can be changed without a sudden
torque or horsepower discontinuity by variably controlling a shift
clutch coupled to the gear set.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a schematic representation of a supercharger
system in accordance with the present invention;
[0015] FIG. 2 is a schematic representation of the interior of the
gearbox of FIG. 1;
[0016] FIG. 3 is a is a schematic representation of the clutch of
FIG. 2;
[0017] FIG. 4 is a second embodiment of the interior of the gearbox
of FIG. 2 in accordance with the present invention;
[0018] FIG. 5 is a third embodiment of the interior of the gearbox
of FIG. 2 in accordance with the present invention;
[0019] FIG. 6 is a fourth embodiment of the interior of the gearbox
of FIG. 2 in accordance with the present invention;
[0020] FIG. 7 is a fifth embodiment of the interior of the gearbox
of FIG. 2 in accordance with the present invention;
[0021] FIG. 8 is a second embodiment of the clutch of FIG. 3 in
accordance with the present invention; and
[0022] FIG. 9 is a third embodiment of the clutch of FIG. 3 in
accordance with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] FIG. 1 illustrates a supercharger system 20 that connects to
and is driven by an internal combustion engine 22. The engine 22
includes a crankshaft 24, which includes a drive pulley 26 affixed
to one end. A belt 28 connects the drive pulley 26 to a driven
pulley 30, which drives the input shaft 32 to a gearbox 34. A
controller 35 is electrically connected to a clutch in the gearbox
34. Preferably, the controller 35 works in combination with the
engine controller, not shown, to coordinate the operation of the
clutch with other engine operations. The internal components of the
gearbox 34 and its clutch will be described below with reference to
FIGS. 2 and 3.
[0024] The gearbox 34 has an output shaft 36, which drives an
impeller 38 of a centrifugal air pump (supercharger) 40. The pump
40 includes an air intake 42, a compression chamber 46, and an air
outlet 44 leading to an intake manifold (not shown) of the internal
combustion engine 22. The supercharger system 20 also includes a
lubrication circuit 48, which has a pump 50 and a cooler 52. The
fluid in the lubrication circuit can be oil or transmission
fluid.
[0025] FIG. 2 illustrates the components internal to the gear box
34. The input shaft 32 drives a first planetary gear set 54. More
particularly, the input shaft 32 is coupled to and drives a first
planet carrier 56, and is also connected to a first ring gear 58
via a one way clutch 60. A first set of planet gears 62, mounted in
the first planet carrier 56, couple a first sun gear 64 to the
first ring gear 58. An electronically controlled clutch 66 is
rotationally connected, via a shaft 65, so as to allow for
selectively coupling and decoupling the first sun gear 64 to the
gear box 34 (which in this configuration is ground). The first ring
gear 58 is rotationally fixed to second ring gear 68 of a second
planetary gear set 70. The second ring gear 68 engages a second set
of planet gears 72, which are mounted on a second planet carrier
74. This second planet carrier 74 is held (rotationally fixed
relative to the gear box 34). The second set of planetary gears 72
also engage a second sun gear 76, which is rotationally fixed to
the output shaft 36. An example of gear ratios for the two
planetary gear sets that one may use is a ratio of ring gear teeth
to sun gear teeth of 1.4 on the first planetary gear set 54, and a
ratio of ring gear teeth to sun gear teeth of 5 on the second
planetary gear set 70. Of course, the actual ratio for a given
vehicle will depend upon the size of the engine, the ratio at the
drive pulley 28 and the amount of supercharger boost desired, among
other factors. For a typical engine, if one has a pulley ratio of
2:1, then the ratio of output to input speed might be 5:1 for the
lower gear ratio and 10:1 for the higher gear ratio.
[0026] FIG. 3 shows a schematic diagram of the shift clutch 66,
which in this embodiment is an electromagnetic particle clutch. The
clutch 66 includes a rotor 78, which is rotationally fixed to the
shaft 65, and a stator 80, which is coupled to the rotor 78 via
bearings 82. A coil 84 is mounted to the stator 80, which are both
rotationally fixed relative to the gear box 34. The annulus between
the rotor 78 and the stator 80 is filled with an iron powder
86.
[0027] The operation of the supercharger system 20 will now be
described with reference to FIGS. 13. When the first sun gear 64 is
held (rotationally fixed relative to the gear box 34) by the clutch
66, as the input shaft 32 drives the first planet carrier 56, the
first planetary gear set 54 in cooperation with the second
planetary gear set 70 causes the output shaft 36 to rotate in the
opposite direction and at a significantly higher rotational
velocity than the input shaft 32. On the other hand, when the
clutch 66 is not activated, the input shaft 32 drives the first
planet carrier 56, and since the first sun gear 64 is not held the
one way clutch engages. This causes the first and second planetary
gear sets 54, 70 to rotate the output shaft 36 again in a reverse
direction from the input shaft 32 and at a higher rotational
velocity, but a significantly lower velocity than when the clutch
66 is engaged.
[0028] This system is particularly advantageous when mounted on an
engine in a vehicle. As the vehicle starts accelerating from a
stop, or slow speed at high throttle angle, the controller 35
activates the clutch 66 and keeps it engaged, so the centrifugal
pump 40 is being driven at the higher gear ratio. When the engine
is running above a particular RPM range, the controller 35 leaves
the clutch off, so the centrifugal pump 40 is driven at the lower
gear ratio. But during the transition between the clutch 66
remaining on and the clutch 66 remaining off, the controller 35
modulates the clutch 66 on and off. By modulating the clutch 66 on
and off, with the clutch beginning as mostly on and gradually
changing to mostly off, until through a transition to the higher
speed range and then leaving clutch off, one obtains a smooth
transition from the initial high speed gearing to the low speed
gearing. Or, as an alternative, the controller 35 actuates the
clutch 66 to allow for controlled slippage to progressively engage
or release the clutch 66. By modulating the clutch 66, undesirable
discontinuities in the engine torque and horsepower during the
transition from low speed to high speed can be avoided.
[0029] Also, while the engine is operating, the oil cooling circuit
48 operates. The pump 50 pumps oil, or transmission fluid if so
configured, from the gear box 34, through a cooler 52, and back
into the gear box 34 in order to cool and lubricate the gears and
clutches.
[0030] A second embodiment of the gear set is shown in FIG. 4. For
this embodiment, similar elements are similarly designated to those
in FIG. 2, but with a 100 series number. The input shaft 32 is
rotationally connected to the planet gear carrier 156 of the first
planetary gear set 154. The planet gear carrier 156 mounts the
planet gears 162, which engage with the first sun gear 164, and the
first ring gear 158. The first ring gear 158 is selectively
restrained by the clutch 66. The clutch 66 is again grounded to the
gear box 34. The first sun gear 164 is rotationally fixed to and
drives the second ring gear 168 on the second planetary gear set
170. A one way clutch 160 also couples the first planet carrier 156
to the second ring gear 168. The second ring gear 168 engages the
second set of planetary gears 172, whose planet carrier 174 is
grounded to the gear box 34. The second set of planetary gears 172,
in turn, engages the second sun gear 176, which is rotationally
coupled to and drives the output shaft 36. The operation of this
embodiment is similar to that of the first where, when the clutch
is engaged, the output shaft 36 rotates in the opposite direction
to the input shaft 32, but at a significantly higher rotational
speed, and when the clutch is not engaged, the output shaft 36 also
rotates in the opposite direction and at a higher speed than the
input shaft 32, but at a lower speed than when the clutch is
engaged.
[0031] A third embodiment of the gear set is shown in FIG. 5. For
this embodiment, similar elements are similarly designated, but
with a 200 series number. The input shaft 32 is rotationally
connected to the planet gear carrier 256 of the first planetary
gear set 254. The planet carrier 256 mounts the planet gears 262,
which engage with the first sun gear 264, and the first ring gear
258, which is selectively restrained by the clutch 66. The clutch
66 is again grounded to the gear box 34. The first sun gear 264 is
rotationally fixed to and drives the second planet gear carrier 274
on the second planetary gear set 270. A one way clutch 260 also
couples the first planet carrier 256 to the second planet gear
carrier 274. The second planet carrier 274 mounts the second set of
planetary gears 272, which engage the second ring gear 268, which,
in turn, is rotationally held by the gear box 34. The second set of
planetary gears 272 also engage the second sun gear 276, which is
rotationally coupled to and drives the output shaft 36. The
operation of this embodiment is similar to that of the first and
second, except the output shaft 36 now rotates in the same
direction as the input shaft 32.
[0032] A fourth embodiment of the gear set is shown in FIG. 6. For
this embodiment, similar elements are similarly designated, but
with a 300 series number. The input shaft 32 is rotationally
connected to the planet gear carrier 356 of the first planetary
gear set 354. The planet carrier 356 mounts the planet gears 362,
which, in turn, engage with the first sun gear 364. The first sun
gear 364 can be rotationally held by the clutch 66. The clutch 66
is grounded to the gear box 34. The planet gears 362 also engage
the first ring gear 358, which is rotationally coupled to the
second planet carrier 374 of the second planetary gear set 370. A
one way clutch 360 is connected between the first planet carrier
356 and the first ring gear 358. The second planet carrier 374
mounts the second set of planetary gears 372, which engage with the
second ring gear 368, which is, in turn, rotationally grounded to
the gear box 34. The second set of planetary gears 372 also engage
with the second sun gear 376, which is rotationally coupled to and
drives the output shaft 36. The operation of this arrangement is
similar to that shown in FIGS. 2 and 4, but with the rotation of
the output shaft 36 in the same direction as the input shaft
32.
[0033] A fifth embodiment of the gear set is shown in FIG. 7. For
this embodiment, similar elements are similarly designated, but
with a 400 series number. The input shaft 32 is rotationally
coupled to the first ring gear 458 of the first planetary gear set
454 and to the second planet carrier 474 of the second planetary
gear set 470. The first ring gear 458 engages the first set of
planet gears 462, which are mounted on the first planet carrier
456. The first planet carrier 456 is coupled to the clutch 66,
which is selectively grounded to the gear box 34. The first set of
planet gears 462 engage the first sun gear 464, which, in turn, is
rotationally coupled to the second ring gear 468. The second ring
gear 468 is coupled to a one way clutch 460, which is grounded to
the gear box 34, and also engages the second set of planet gears
472. The second set of planet gears 472 are mounted on the second
planet carrier 474 and engage the second sun gear 476, which, in
turn, couples to and drives the output shaft 36. The operation of
this embodiment is similar to the previous embodiments with the
output shaft rotating in the same direction as the input shaft.
[0034] A second embodiment of the electronically controllable
clutch is shown in FIG. 8, which, in this embodiment, is an
electric ball/ramp clutch. For this embodiment, similar elements
are similarly designated, but with a 500 series number. The clutch
566 rotationally couples to the shaft 65 via clutch discs 588 and a
ball/ramp mechanism 589. Corresponding clutch plates 590 are
interleaved with the clutch discs 588 and rotationally fixed to the
gear box 534. A coil 584 is also mounted to the gear box 534. By
activating the coil 584, the clutch 566 will rotationally fix the
shaft 65 to the gear box (ground) 534.
[0035] A third embodiment of the electronically controllable clutch
is shown in FIG. 9, which in this embodiment is an electric cone
clutch. For this embodiment, similar elements are similarly
designated, but with a 600 series number. The clutch 666
rotationally couples to the shaft 65 via a U-shaped stator member
680. The stator member 680 includes friction material 686 that is
adjacent to a surface of the gear box 634. A coil 684 also mounts
to the gear box 634. When the coil 684 is activated, the friction
material 686 comes into contact with the wall of the gear box 634
and grounds the shaft 65 to the gear box 634.
[0036] While certain embodiments of the present invention have been
described in detail, those familiar with the art to which this
invention relates will recognize various alternative designs and
embodiments for practicing the invention as defined by the
following claims. For example, there are other gear set
configurations and other controllable clutches that can be used to
drive the engine supercharger.
* * * * *